Most "welcome bonus" eligibility rules ask one question: has this account deposited before? Underdog’s welcome bonus code asks a different one — has this identity ever registered at all, deposit or not — and that stricter bar is the part most roundups of SDS, GRINDERS, HANDLE, and VIBONUS skip past on their way to the headline dollar figure.
The Bar Is Registration, Not Deposit
Underdog’s own terms disqualify any device or identity that has previously created an account, whether or not that account ever funded a lineup. Someone who signed up for Underdog two years ago, never deposited, and forgot the login exists is not a fresh welcome candidate — the account already exists in Underdog’s records, and that’s the whole test. This is stricter than a typical "first deposit only" rule, and it’s the single most common reason a code that looks correct still doesn’t pay out.
Check before creating a new login. If there is any chance an old Underdog account exists under the same name, email, phone number, or device, that history — not the promo code entered this time — decides welcome-bonus eligibility.
What a Genuinely New Account Gets
Clear the registration bar and the mechanics are a single-deposit match, not a multi-deposit sequence: a $10 minimum first deposit unlocks a 50% match in bonus funds, capped at $1,000. A $200 deposit returns $100; anything at $2,000 or above still caps at the full $1,000. It applies once, to that first deposit — there is no second- or third-deposit code carrying the match further, unlike the multi-deposit structures some sportsbooks run.
Minimum qualifying deposit: $10
Match: 50% of first deposit, up to $1,000
Playthrough: 1x before bonus funds convert to withdrawable balance
Applies to: one deposit only, not a sequence
Keep Your Million Runs Its Own Clock
Qualifying for the deposit match also unlocks eligibility for Keep Your Million, but that game has timing rules of its own, separate from the deposit match itself. The qualifying $10 deposit has to happen within 7 days of becoming eligible to activate the game at all. Once it activates, the account gets up to 60 days to work through all 20 higher-or-lower player-projection questions, deciding how much of a virtual $1 million balance to risk on each one before whatever survives converts to real bonus funds. Miss either window and the eligibility lapses — it isn’t something that can be picked back up later on the same signup.
Which Code String Doesn’t Matter
SDS, GRINDERS, HANDLE, VIBONUS, and the handful of other partner strings circulating this September all point at the identical package described above. None unlocks a bigger match or a longer Keep Your Million window than another — the code only tells Underdog which media site referred the signup, the same tracking function PrizePicks’s partner codes serve. Picking one over another is a matter of which page happened to be open, not which offer is better.
Where It Doesn’t Run
The welcome offer itself has not been available in Maryland, Michigan, New Jersey, New York, Ohio, or Pennsylvania — a narrower list than the states where Underdog is blocked outright: Connecticut, Hawaii, Idaho, Iowa, Louisiana, Maine, Montana, Nevada, and Washington. A state can carry live Pick’em products and still not carry this particular welcome promotion. Age gates apply on top: 18+ in most states, 19+ in Alabama and Nebraska, 21+ in Arizona, Massachusetts, and Virginia. This is promotional value on an entry fee, not income — confirm the live terms in-app before funding a first deposit.